Just months after announcing it intended to offer a range of cafe racers based around the Buell Blast's single-cylinder engine, Mac Motorcycles was blindsided by Harley's declaration that large-scale production of the Blast would cease. Left without a cheap supply of air-cooled singles, Mac is considering the liquid-cooled engine from the Yamaha XT660Z. That would mean more power if less pure looks. Good idea?>

The Blast's carbureted 492cc engine makes 34bhp at 6,500rpm and 30lb/ftof torque at 3,200rpm. In comparison, the 660cc fuel-injected Yamahaengine makes 48bhp at 6,000rpm and 43lb/ft of torque. Like the Harleyunit, reliability is almost a given, upgrades are plenty, repair ischeap and sources for parts are widespread. Mac says the swap wouldn'thave a noticeable impact on the end price and we wouldn't expect muchof a weigh difference, despite the addition of a radiator.

A more significant concern of Mac's appears to be the looks. Thesedetails and this image were emailed out to potential customers to gaugetheir reaction to the change. While purists will undoubtedly bemoan thelack of fins and the addition of all sorts of pipes and other addenda,we actually prefer the way the Yamaha engine looks in the frame. Itadds a welcome dose of the contemporary to this Mac Spud's classiclooks, something that could give it added appeal to buyers in theirtwenties and thirties. That could be a very good thing. AsHarley-Davidson is finding out, Baby Boomers stopped floating themotorcycling industry about this time last year.